Abstract: A method for producing a vapor stream from waste plastic comprises providing a waste plastic feedstock into a reactor containing one or more residues produced from a previously heated source of waste plastic, and heating the waste plastic feedstock in the reactor to a temperature from about 125° C. to 500° C. to generate a vapor containing one or more hydrocarbons. The waste plastic feedstock can have a calcium to sodium mass ratio from about 0.0001 to 400 as measured by inductively-coupled plasma (ICP) spectrometry. The catalytic activity in the reactor may be provided through one or more constituent elements in the waste plastic feedstock or the one or more residues produced from the previously heated source of waste plastic.

Abstract: A watercraft propulsion system for moving a watercraft along a waterway having a bottom and a surface, wherein the watercraft presents a port side and a starboard side. The watercraft propulsion system comprises a boom assembly having a proximal end and a distal end, with the proximal end being rotatably coupled with the watercraft. The watercraft additionally comprises a wheel mounted to the distal end of the boom. The wheel includes at least one generally radially-extending blade assembly, with the blade assembly comprising a primary blade and a secondary blade. The secondary blade extends at an angle with respect to the primary blade so as to present a fluid channel between the primary blade and the secondary blade.

Abstract: A cutterhead for dredging water-bed material from a body of water. The cutterhead comprises a shroud presenting a front margin for receiving water-bed material into an interior space of the shroud. The shroud additionally includes a port from which water-bed material can be removed from the interior space of the shroud. The cutterhead additionally comprises a rotatable cutterbar at least partially received within the interior space of the shroud. The cutterhead further comprises a debris guard positioned between the cutterbar and the port. The debris guard is operable to filter the water-bed material removed from the shroud through the port. At least a portion of the debris guard that faces the cutterbar includes a concave shape.

Abstract: A dewatering system for separating a slurry into solid material and effluent water. The dewatering system comprises a plurality of support frames arranged to enclose an interior space of the dewatering system, with the interior space being configured to receive the slurry. The dewatering system further includes geo-fabric material positioned on a portion of the support frames, with the geo-fabric material being configured to filter the slurry received within the interior space, such that effluent water permeates through the geo-fabric material and is discharged from the interior space. The dewatering system further comprises a dump door assembly associated with at least one of the support frames, with the dump door assembly including a plurality of hatches configured to selectively open to allow effluent water to be discharged from the interior space of the dewatering system.

Abstract: A cutterhead for dredging a body of water. The cutterhead comprising a shroud including a top wall, a bottom wall, and two sidewalls each extending between the top and bottom walls. The cutterhead additionally comprises a rotatable cutterbar at least partially received within an interior space presented by the shroud, a first water-jet bar extending along a portion of the top wall of the shroud, and a second water-jet bar extending along at least a portion of one of the two sidewalls. The cutterbar and the water-jet bars are configured to generate a slurry of fluidized material from the water-bed.

Abstract: An apparatus for removing floating waterbourne debris. The apparatus includes a capture section comprising a carrier and a motive member mounted on the carrier, with the motive member adapted to contact and direct floating debris rearwardly. The apparatus further includes a collection and pumping section positioned rearward of the capture section for collecting and removing debris directed from the capture section. The collection and pumping section includes a hopper having opposed first and second ends, the first end thereof positioned adjacent the motive member and comprising an opening adapted to receive debris directed by the motive member, and the second end presenting a port for passing debris therethrough, and a pump mounted to the hopper adjacent the port and in fluid communication with the hopper for transporting the debris received from the hopper to a remote location.

Abstract: A method and apparatus for dredging sediment from aquatic environments and cutting aquatic vegetation therein includes using a cutterhead mounted to a dredge. The cutterhead may be mounted to a shroud, the cutterhead including a rotating drum having an array of teeth assemblies which auger cut vegetation toward a port in the shroud for discharge via a pump. The shroud also includes stationary cutterbars having cutterbar teeth assemblies. The teeth assemblies preferably include back-to-back tooth pairs wherein individual teeth have a flat backside and a raised or convex front side which may be provided with serrated cutting margins. Using back-to-back tooth pairs enables cutting of more types and sizes of aquatic vegetation, reducing downtime due to clogging, bending or breakage versus conventional single teeth cutterheads. The shroud may include an upwardly and/or forwardly extending shield along its top front edge to deflect water and/or vegetation back toward the drum.

Abstract: A method and apparatus for dredging sediment from aquatic environments and cutting aquatic vegetation therein includes using a cutterhead mounted to a dredge. The cutterhead may be mounted to a shroud, the cutterhead including a rotating drum having an array of teeth assemblies which auger cut vegetation toward a port in the shroud for discharge via a pump. The shroud also includes stationary cutterbars having cutterbar teeth assemblies. The teeth assemblies preferably include back-to-back tooth pairs wherein individual teeth have a flat backside and a raised or convex front side which may be provided with serrated cutting margins. Using back-to-back tooth pairs enables cutting of more types and sizes of aquatic vegetation, reducing downtime due to clogging, bending or breakage versus conventional single teeth cutterheads. The shroud may include an upwardly and/or forwardly extending shield along its top front edge to deflect water and/or vegetation back toward the drum.

Abstract: A cutterhead for cutting aquatic vegetation, includes a cutterhead shroud, stationary teeth secured to the shroud, and a drum rotatably mounted within the shroud and bearing a flight of vanes cooperating with the teeth to cut vegetation. In accordance with the non-binding aspect of the cutterhead, each vane has an edge that rises gradually from a trailing end adjacent (during drum rotation) to a stationary tooth, to provide a clearance area adjacent the vane into which a respective tooth may be deflected during cutting without impinging upon an associated vane, and thus without causing binding of the cutterhead in the event of such deflection. Each vane may have a curvilinear edge extending from its cutting end to a surface of the drum at its trailing end. The edge defines a two-dimensional profile having a trailing end tangent forming an angle of not more than 70 degrees with the drum.

Abstract: A cutterhead for cutting aquatic vegetation, includes a cutterhead shroud, stationary teeth secured to the shroud, and a drum rotatably mounted within the shroud and bearing a flight of vanes cooperating with the teeth to cut vegetation. In accordance with the non-binding aspect of the cutterhead, each vane has an edge that rises gradually from a trailing end adjacent (during drum rotation) to a stationary tooth, to provide a clearance area adjacent the vane into which a respective tooth may be deflected during cutting without impinging upon an associated vane, and thus without causing binding of the cutterhead in the event of such deflection. Each vane may have a curvilinear edge extending from its cutting end to a surface of the drum at its trailing end. The edge defines a two-dimensional profile having a trailing end tangent forming an angle of not more than 70 degrees with the drum.